1、Designation:D2255/D2255M09(Reapproved 2020)Standard Test Method forGrading Spun Yarns for Appearance1This standard is issued under the fixed designation D2255/D2255M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last re
2、vision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONCotton yarn appearance standards were first adopted in 1938 and revised in 1964,with Series IIIbeing revised again in 1975.The 19
3、64 boards had different yarn sizes for the four-grade exhibits oneach board.The 1975 Series III board used the same yarn number for each grade.The appearance grade of yarn is based on the composite evaluation of several factors,such asunevenness,fuzziness,and neppiness.The differences in the yarn nu
4、mbers in the 1964 standards alongwith the differences in other factors distort the comparison between grades and makes grading moredifficult.To overcome this shortcoming,in 1975 the Series III board was revised using the same size yarnfor all four grades.After evaluating the improvements,it was deci
5、ded to revise all of the series usinga mid-range yarn number for each grade in the series,and narrow the range in the most active series.This was accomplished by adding a new board,Series VI.Anear mid-range yarn number was selectedto represent equal steps between adjacent grades for all the factors
6、considered in yarn appearancegrading.These yarns were produced with current commercial manufacturing equipment and practices.Finally,to obtain better yarn definition and better reproducibility from set to set,it was decided touse offset photo printing.Shortly after these new boards were published in
7、 1979,it became apparent that in the Series II-79Board the A and B grades were not clearly defined and appeared to be switched.This was correctedin the 1987 Series II Board.In 1987 a world wide survey was conducted on how the Yarn Appearance Boards were being used.From responses it became apparent t
8、hat the boards are being used for grading yarns other than 100%cotton combed or carded yarns.Respondents were using the boards to grade yarn blends,ring spunyarns,open-end spun yarns and other spinning systems.The boards are used both for process qualitycontrol and customer acceptance.In view of the
9、 above findings,it was decided to revise the method to include grading of all singlespun yarns.1.Scope1.1 This test method covers the grading of singles spunyarns for appearance.1.2 This test method does not apply to plied yarns.1.3 The values stated in either inch-pound or SI units are tobe regarde
10、d separately as the standard.The values stated ineach system are not exact equivalents,therefore,each systemmust be used independently of the other.Combining valuesfrom the two systems may result in non-conformance with thestandard.1.4 This standard does not purport to address all of thesafety conce
11、rns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.21.5 This international standard was developed in accor-dance with inter
12、nationally recognized principles on standard-ization established in the Decision on Principles for the1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition approved Feb.1,2020.Published
13、February 2020.Originallyapproved in 1964.Last previous edition approved in 2013 as D2255 09(2013)1.DOI:10.1520/D2255_D2255M-09R20.2The requirements for the appearance of cotton yarns are covered in TolerancesD2645,Roller-Drafted Yarns.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,We
14、st Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trad
15、e Organization Technical Barriers to Trade(TBT)Committee.Development of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:3D123 Terminology Relating to TextilesD2258 Practice fo
16、r Sampling Yarn for TestingD2645 Tolerances for Yarns Spun on the Cotton or WorstedSystemsD3888 Terminology for Yarn Spinning SystemsD3990 Terminology Relating to Fabric DefectsD4849 Terminology Related to Yarns and Fibers2.2 ASTM Adjuncts:4Spun Yarn Appearance Standards(6 Boards with Photos)3.Terminology3.1 For definitions of textile terms used in this method:bunch,cover,fuzz,nep,slub,thick place,thin place,and yarnappearance,refer to Terminology D4849.For other textileterms used in this test m
